Prior to the present invention, there have existed mixing devices such as thermostatically controlled valves responsive to a manual setting, in which the valves controling respective flows of hot and cold water in the respective hot water inlet conduit and cold water conduit, are typically butter-fly valves as in the U.S. Pat. No. 2,463,640 to Plett, and longitudinally-movable valves spring-biased, and other longitudinally-movable and variable-channeled valve structures as typically illustrated by U.S. Pat. No. 3,661,181, any and all of which fail to provide for subjective accurate estimation and adjustment to a specific temperature, much less acheiving such devoid of loss of volume adjustment during such variation, and devoid of obtaining full pressure throughout. Also, a separate volume control and separate ratio control are not readily obtainable, much less with separate controls being readily and conveniently simultaneously accessible. Thermostatically controlled mechanisms are highly subject to malfunctioning and are of poor durability, and also the cost of production of such mechanisms is normally prohibitive. Also, such prior devices are adaptable and reserved for installation solely in the initial building of a house or laboratory or the like. In addition, however, and more importantly, both improved sealing against unwanted flow through a valve mechanism as well as greater life or durability of the dependable nature thereof are desired for such a regulator device in order that corrosion of water-containing chemicals and/or extended wear over prolonged usage does not substantially alter the degree of precision in fine adjustments or flow from the respective hot and cold water conduits.